Proteomic Analyses Identify Therapeutic Targets in Hepatocellular Carcinoma

Hepatocellular Carcinoma: Old and Emerging Therapeutic Targets

Liver cancer, predominantly hepatocellular carcinoma (HCC), globally ranks sixth in incidence and third in cancer-related deaths. HCC risk factors include non-viral hepatitis, alcohol abuse, environmental exposures, and genetic factors. No specific genetic alterations are unequivocally linked to HCC tumorigenesis. Current standard therapies include surgical options, systemic chemotherapy, and kinase inhibitors, like sorafenib and regorafenib. Immunotherapy, targeting immune checkpoints, represents a promising avenue. FDA-approved checkpoint inhibitors, such as atezolizumab and pembrolizumab, show efficacy, and combination therapies enhance clinical responses. Despite this, the treatment of hepatocellular carcinoma (HCC) remains a challenge, as the complex tumor ecosystem and the immunosuppressive microenvironment associated with it hamper the efficacy of the available therapeutic approaches. This review explores current and advanced approaches to treat HCC, considering both known and new potential targets, especially derived from proteomic analysis, which is today considered as the most promising approach. Exploring novel strategies, this review discusses antibody drug conjugates (ADCs), chimeric antigen receptor T-cell therapy (CAR-T), and engineered antibodies. It then reports a systematic analysis of the main ligand/receptor pairs and molecular pathways reported to be overexpressed in tumor cells, highlighting their potential and limitations. Finally, it discusses TGFβ, one of the most promising targets of the HCC microenvironment.

Advancing beyond reverse transcriptase inhibitors: The new era of hepatitis B polymerase inhibitors

Hepatitis B virus (HBV) is a genetically diverse blood-borne virus responsible for chronic hepatitis B. The HBV polymerase plays a key role in viral genome replication within the human body and has been identified as a potential drug target for chronic hepatitis B therapeutics. However, available nucleotide reverse transcriptase inhibitors only target the reverse transcriptase domain of the HBV polymerase; they also pose resistance issues and require lifelong treatment that can burden patients financially. In this study, various chemical classes are reviewed that have been developed to target different domains of the HBV polymerase: Terminal protein, which plays a vital role in the formation of the viral DNA; Reverse transcriptase, which is responsible for the synthesis of the viral DNA from RNA, and; Ribonuclease H, which is responsible for degrading the RNA strand in the RNA-DNA duplex formed during the reverse transcription process. Host factors that interact with the HBV polymerase to achieve HBV replication are also reviewed; these host factors can be targeted by inhibitors to indirectly inhibit polymerase functionality. A detailed analysis of the scope and limitations of these inhibitors from a medicinal chemistry perspective is provided. The structure-activity relationship of these inhibitors and the factors that may affect their potency and selectivity are also examined. This analysis will be useful in supporting the further development of these inhibitors and in designing new inhibitors that can inhibit HBV replication more efficiently.

Comprehensive Analysis of HMCN1 Somatic Mutation in Clear Cell Renal Cell Carcinoma

Background: Renal cell carcinoma (RCC) is a common malignancy of the genitourinary system and clear cell renal cell carcinoma (ccRCC) is the most representative subtype. The morbidity and mortality of ccRCC have gradually risen during recent years; however, the pathogenesis and potential biomarkers remain unclear. The purpose of our study was to find out prognostic genes correlated with somatic mutation and the underlying mechanisms of HMCN1 mutation in ccRCC. Methods: Somatic mutation data of two ccRCC cohorts were acquired from TCGA and cBioPortal. Genes frequently mutated in both datasets were extracted, from which tumor mutation burden and survival analysis revealed three prognostic genes. Further comprehensive analysis of HMCN1 mutation was carried out to identify differentially expressed genes and apply functional annotations. The correlation of HMCN1 mutation and tumor immunity was also evaluated. Results: HMCN1, SYNE1, and BAP1 mutations were associated with both tumor mutation burden and clinical prognosis in ccRCC. Gene enrichment analysis suggested the effects of HMCN1 mutation on biological processes and pathways linked to energy metabolism. HMCN1 mutation was also correlated with anti-tumor immunity. There were several limitations in the sample size and cohort availability of the present computational study. Conclusions: The present results inferred that HMCN1 mutation might have an important clinical significance for ccRCC patients by regulating metabolism and the immune microenvironment.